textproduct: Rapid City

KEY MESSAGES

- Strong winds expected today. A High Wind Warning continues for most of western SD.

- Snow expected on Wednesday, turning to rain. Light freezing rain possible Wednesday night.

- Turning colder with chances for snow Thursday through Saturday.

DISCUSSION

(Today Through Monday) Issued at 338 AM MST Tue Dec 9 2025

Upper air analysis shows obstinate northwest flow across the western/central CONUS. Water vapor shows a strong wave crossing the northern Rockies, quickly approaching the northern High Plains. Surface analysis indicates low pressure just north of MT, quickly heading toward ND. As the low approaches this morning, winds will increase, gusting to over 60 mph through the day. The best chance for strong winds will be across most of the western SD plains. Locations across the NE WY zones will also see gusty winds. Some models show the potential for gusts over 50kt, but overall consensus is that it will stay below that threshold. There are newer indications that +50kt gusts could develop over the eastern half of the Black Hills. Will have dayshift take a closer look with 12z runs to see if a late update is needed with headline adjustments. Otherwise, the High Wind Warning looks to be in good shape. A cold front will cross the area late this afternoon or early evening. Low level mixing w/ CAA will keep wind momentum going after sunset. This system will also bring light rain to the area, especially ahead of the frontal boundary. Snow is expected across the Black Hills, but temps will be above freezing except over the highest terrain. QPF will be light. Winds will gradually decrease overnight as surface high pressure builds across the Dakotas. The next system is following closely behind...and could bring interesting weather for Wednesday. Low pressure over the MT Rockies on Wednesday will slide SE, arriving to the CWA on Thursday. Strong overrunning will support 700mb frontogenesis/isentropic lift on Wednesday, bringing widespread light snow in the morning, then becoming rain through the day as warmer air advects in from the west. The broad band of snow over central South Dakota could become freezing rain as warmer air aloft noses in. Overall QPF amounts look to be light...under a tenth of an inch, which will limit ice accumulation. But will keep an eye on this for potential impacts. A cold front is then expected to push through Thursday, then another reinforcing cold front Thursday night. Though it looks like snow will hang around on Thursday and into Friday, it's still a bit uncertain what snow amounts will look like. There does seem to be better agreement between the ECM and GFS...bringing light to somewhat moderate amounts over NE WY/Black Hills late Thursday, then moderate or heavy amounts over NW SD through Friday and Saturday. There is a lot to track over the next few days.

AVIATION

(For the 12Z TAFS Through 12Z Wednesday Morning) Issued At 338 AM MST Tue Dec 9 2025

Areas of MVFR/IFR conditions due to lower clouds/ra/sn will affect northeast WY/northwest SD today. Otherwise VFR conditions expected over southwest into south-central SD. Strong winds gusting to +50kt are expected across much of the western SD plains today.

UNR WATCHES/WARNINGS/ADVISORIES

SD...High Wind Warning from 8 AM MST /9 AM CST/ this morning to 2 AM MST /3 AM CST/ Wednesday for SDZ001-002-012>014-025>027- 030>032-041>044-046-047-049-072>078. WY...High Wind Warning from 8 AM this morning to 2 AM MST Wednesday for WYZ060.